The Encryption of messages by Whatsapp makes it so that 3rd person parties are not privy to your information, but could this also work the other way round?

According to Britain's home Secretary Amber Rudd, Encryption of messages on services such as WhatsApp is “completely unacceptable” in the fight against terror.

She added that Intelligence agencies must have access to the messages and social media sites must do more to police extremist material.

This is subsequent to the incident at Westminster, where terrorist Khalid Masood used WhatsApp seconds before launching Wednesday's attack, but agencies are unable to see what was communicated.

Ms Rudd added that the likes of Google, which runs the social video sharing platform YouTube, and other smaller sites such as WordPress must realise that they are now publishing companies and take more responsibility for taking down extreme material.

In an interview with BBC One she said: "It is completely unacceptable, there should be no place for terrorists to hide.

"We need to make sure that organisations like WhatsApp, and there are plenty of others like that, don't provide a secret place for terrorists to communicate with each other.

"It used to be that people would steam-open envelopes or just listen in on phones when they wanted to find out what people were doing, legally, through warrantry.

"But on this situation we need to make sure that our intelligence services have the ability to get into situations like encrypted WhatsApp."

She added that she would be meeting with some of these companies

"What these companies have to realise is that they are now publishing companies, they are not technology companies, they are platforms and we need to make sure that that (hosting extremist material) stops," she said.

"You are right, we will not resile from taking action if we need to do so."

She added, "I would rather get a situation where we get all these people around the table agreeing to do it.

"I know it sounds a bit like we're stepping away from legislation but we're not.

"What I'm saying is the best people who understand the technology, who understand the necessary hashtags to stop this stuff even being put up, not just taking it down, but stopping it being put up in the first place, are going to be them."